This invention relates to the protection of vehicular occupants against harmful radiation, and more particularly, to the protection of automobile occupants against harmful ultraviolet radiation.
Ultraviolet radiation, especially in the A, B and C bands, can be harmful to animals, including humans. In order to protect against this kind of radiation, it is necessary to limit the amount of glass surface commonly found in automotive vehicles. At the same time, it is desirable to expand the glass surface in order to promote visibility.
Accordingly, it is an object of the invention to provide protection against the exposure of automotive occupants to harmful radiation while simultaneously not interfering with the desire to increase the amount of light transmittive surface in order to promote automotive visibility.
There have been numerous attempts to provide ultraviolet protection. An illustrative example is provided by U.S. Pat. No. 6,235,271, which issued to Luther et al., on May 22, 2001. Luther et al. disclose a sunprotection agent, which is especially suitable for use in pharmaceutical or cosmetic applications, containing a micronized organic UV absorber, and a non-micronized UV absorber and/or an inorganic-micropigment, together with a polymeric hollow sphere additive and/or xanthan and/or polyvinylpyrrolidone.
Another preparation for ultraviolet protection is set forth in U.S. Pat. No. 4,804,531 which issued to Grollier on Feb. 14, 1989. Grollier discloses a cosmetic screening composition containing a UV screen in combination with a polymer obtained by block polymerization in emulsion and its use for the protection of the human epidermis against ultraviolet radiations.
Still another composition for UV protection is provided by U.S. Pat. No. 4,524,061, which issued to Cho et al. on Jun. 18, 1985. This patent is directed to a polymeric sunscreen agent of interpolymers including an olefinic p-aminobenzoate devoid of hydroxy substitution, N-vinylpyrrolidone, and at least a vinyl lactam monomer.
There also have been numerous attempts to provide ultraviolet protection for glass, but none of these achieve the advantages and simplicity of the invention. The prior art includes the following patents: U.S. Pat. No. 6,220,059, xe2x80x9cMethod of Coating a UV-fiber With Blocking Layers and Charging the Fiber With Hydrogen Or Deuteriumxe2x80x9d; U.S. No. 6,159,608,
xe2x80x9cThermoplastic Interlayer Filmxe2x80x9d; U.S. Pat. No. 6,143,417, xe2x80x9cContamination-Resistant Float Glassxe2x80x9d; U.S. Pat. No. 6,138,663, xe2x80x9cCooking Apparatus Containing A Window That Is A Contamination-Resistant Float Glassxe2x80x9d; U.S. Pat. No. 6,122,093, xe2x80x9cReduced Ultraviolet Radiation Transmitting, Safety Protected Electrochromic Glazing Assemblyxe2x80x9d; U.S. Pat. No. 6,121,354, xe2x80x9cHigh Performance Single-Component Sealantxe2x80x9d; U.S. Pat. No. 6,117,497, xe2x80x9cSolid Surface Modification Method and Apparatusxe2x80x9d, U.S. Pat. No. 6,022,624, xe2x80x9cPartially Crystallizing Lead-Free Enamel Composition for Automobile Glassxe2x80x9d; U.S. No. 5,986,797, xe2x80x9cReduced Ultraviolet Radiation Transmitting, Safety Protected Electrochromic Glazing Assemblyxe2x80x9d; U.S. Pat. No. 5,972,565, xe2x80x9cFlexographic Printing Forms Having Resistance to UV-Hardenable Printing Inksxe2x80x9d; U.S. Pat. No. 5,948,594, xe2x80x9cFlexographic Printing Forms for UV-Hardenable Printing Inksxe2x80x9d; U.S. Pat. No. 5,925,160, xe2x80x9cPartially Crystallizing Lead-Free Enamel Composition For Automobile Glassxe2x80x9d; U.S. Pat. No. 5,908,585, xe2x80x9cElectrically Conductive Transparent Film And Coating Composition For Forming Such Filmxe2x80x9d; U.S. Pat. No. 5,864,419, xe2x80x9cNear-Infrared Reflecting, Ultraviolet Protected, Safety Protected, Electrochromic Vehicular Glazingxe2x80x9d, U.S. Pat. No. 5,846,279, xe2x80x9cProcess for Producing A Contamination-Resistant Float Glassxe2x80x9d; U.S. Pat. No. 5,792,560, xe2x80x9cThermoplastic Interlayer Filmxe2x80x9d; U.S. Pat. No. 5,783,507, xe2x80x9cPartially Crystallizing Lead-Free Enamel Composition For Automobile Glassxe2x80x9d; U.S. Pat. No. 5,680,245, xe2x80x9cReduced Ultraviolet Radiation Transmitting, Electrochromic Assemblyxe2x80x9d; U.S. Pat. No. 5,641,716, xe2x80x9cGlass Production Method Using Ilmenitexe2x80x9d; U.S. No. 5,629,365, xe2x80x9cUV-Absorbing Polymer Latexxe2x80x9d; U.S. Pat. No. 5,610,108, xe2x80x9cReducing Melt Borosilicate Glass Having Improved UV Transmission Properties And Water Resistance And Method of Usexe2x80x9d; U.S. Pat. No. 5,578,378, xe2x80x9cAnti-Fogging Coating Composition, Product Coated With Said Composition And Method for Preparation of Said Productxe2x80x9d; U.S. Pat. No. 5,547,904, xe2x80x9cBorosilicate Glass Having Improved UV Transmission, Thermal and Chemical Properties and Method of Making and Using Samexe2x80x9d; U.S. Pat. No. 5,523,877, xe2x80x9cReduced Near-Infrared Radiation Transmitting Ultraviolet Protected, Safety Protected Electrochromic Vehicular Glazingxe2x80x9d; U.S. Pat. No. 5,523,263, xe2x80x9cGlass Production Method Using Ilmenitexe2x80x9d; U.S. Pat. No. 5,480,722, xe2x80x9cUltraviolet Ray Absorbent Glass and Method For Preparing the Samexe2x80x9d; U.S. Pat. No. 5,385,872, xe2x80x9cUltraviolet Absorbing Green Tinted Glassxe2x80x9d; U.S. Pat. No. 5,364,433, xe2x80x9cOptical Member of Synthetic Quartz Glass For Excimer Lasers and Methods For Producing Samexe2x80x9d; U.S. Pat. No. 5,355,245, xe2x80x9cUltraviolet Protected Electrochemichromic Rearview Mirrorxe2x80x9d; U.S. Pat. No. 5,249,076, xe2x80x9cOptical Filter Structurexe2x80x9d; U.S. No. 5,240,886, xe2x80x9cUltraviolet Absorbing, Green Tinted Glassxe2x80x9d; U.S. Pat. No. 5,239,406, xe2x80x9cNear-Infrared Reflecting, Ultraviolet Protected, Safety Protected, Electrochromic Vehicular Glazingxe2x80x9d; U.S. Pat. No. 5,214,008, xe2x80x9cHigh visible, Low UV and Low IR Transmittance Green Glass Compositionxe2x80x9d; U.S. Pat. No. 3,115,346, xe2x80x9canti-Scatter, Ultraviolet Protected, Anti-Misting, Electro-Optical Rearview Mirror; U.S. Pat. No. 5,098,948, xe2x80x9cWater-Based Protective Compositions for Coating Films and Preparation Processes Thereofxe2x80x9d; U.S. Pat. No. 5,077,133, xe2x80x9cInfrared And Ultraviolet Radiation Absorbing Green Glass Compositionxe2x80x9d; U.S. Pat. No. 5,045,509, xe2x80x9cUV-Transparent Glassxe2x80x9d; U.S. Pat. No. 4,792,536, xe2x80x9cTransparent Infrared Absorbing Glass And Method of Makingxe2x80x9d; U.S. Pat. No. 4,649,062, xe2x80x9cUltraviolet Radiation Curable Vehicle For Ceramic Colors, Composition and Methodxe2x80x9d; U.S. Pat. No. 4,326,214, xe2x80x9cThermal Shock Resistant Package Having an Ultraviolet Light Transmitting Window For a Semiconductor Chipxe2x80x9d.
In accomplishing the foregoing and related objects, the invention provides a light-transmissive surface which permits unimpeded visual radiation, but simultaneously serves as a protective shield against ultraviolet (UV) radiation, particularly in the UV-A, UV-B and UV-C bands.
The invention functions by absorbing the UV portion of radiation below 315 nanometers (xe2x80x9cnmxe2x80x9d) of the A, B and C bands, and provides a method for the manufacture of such a light transmissive surface, as well as for the use of such surface as automotive glass.
The light-transmissive medium of the invention includes means for permitting unimpeded visual radiation, and means included for simultaneously serving as a protective shield against ultraviolet radiation.
The light-transmissive medium can include a conjugated double-bond polymer, selected from the class consisting of alkenes and arenes.
The light-transmissive medium can include the conjugated double-bond polymer in another polymeric material comprising an interlayer for glass, such as polyvinyl butyral.
In a method of the invention for providing a light-transmissive surface, the steps include (a) providing a medium that shields ultraviolet radiation; (b) combining the medium with a substance that provides general radiation transmission. The medium can be mixed with the substance and be selected from the class of conjugated multiple-bond polymers.
In the method, the medium can be a salt that absorbs UV radiation, such as cerium aluminate.
In a method of the invention for providing a light-transmissive material, the steps include (a) providing a substance that shields ultraviolet radiation; (b) providing a substance that is generally radiation transmissive; and (c) combining the substances of steps (a) and (b).
The method further includes the step of casting the combined substances into a specified shape, such as automotive glass.
In the method, the substance that shields ultraviolet radiation can have conjugate, multiple bonds selected from the class consisting of alkenes and arenes.
In an apparatus for protecting against harmful radiation, the apparatus can have an interior which is subject to radiation exposure and include a material for limiting the extent to which harmful components of radiation can penetrate the interior.
The apparatus can be an automobile with glass paneling which has been modified to curtail the transmission of ultraviolet radiation.
In accordance with one aspect of the invention, the light transmissive medium, such as glass is mixed, for example, by combination with a material that inhibits UV transmission while simultaneously permitting unimpeded transmission of the ordinary visual components.